Publications

The main producing mechanism in the Duri Steamflood (DSF) after steam breakthrough is gravity drainage. The steam that is injected after steam breakthrough is to maintain the downward growth of the expanding steam chest and to compensate for heat losses to the formation and produced fluid. If there is enough heat in the steam chest to account for the heating requirements, then steam injection may be terminated. The pattern producers would probably produce at a lower rates, but the oil sales may increase because no steam had to be generated for that pattern (i.e. no oil fuel). In these cases, potential exists for converting the observation wells and injectors to producers.As the steamflood matures in a pattern, the information derived from a temperature observation well (TOW) becomes less valuable. At some point in time the net present value for the pattern can be increased by losing data that the TOW can provide, and converting to an oil producer. Field results in the more mature areas of the DSF have shown that there is little interference from oil producers that are in close proximity. It is assumed therefore that conversion of TOW to producer will have little to no effect on the productivity of the existing pattern producers.Conversion of an injector to a producer is a trickier proposition than converting a TOW. All that is lost when converting a TOW is information, but once an injector is converted there is no effective means of delivering heat to the pattern. The critical parameter for the success of the injector well conversions is that there is sufficient steam coverage in the major flow units and enough heat already present to sustain the gravity drainage producing mechanism.Field results in Areas 1, 2, and 3 indicated that converting idle wells has gained oil production at an average of 60 BOPD per well and there is no significant sand production from most of the wells even though the wells were completed without using screen liner as a sand control method like other normal producers in DSF.